Atrial fibrillation is the most common cardiac arrhythmia and symptoms overlap with physiological sensations of anxiety. Patients with atrial fibrillation can demonstrate anxiety sensitivity even in the absence of actual atrial fibrillation symptoms. Interoceptive exposure is effective in treating anxiety sensitivity, and recently, mindfulness has been proposed as an enhancement strategy to facilitating inhibitory learning in exposure therapy. This pragmatic study piloted a brief mindfulness and interoceptive exposure treatment for anxiety sensitivity in atrial fibrillation. Eight participants with atrial fibrillation and elevated anxiety sensitivity from a hospital cardiology department participated in the treatment. Anxiety sensitivity significantly decreased during the course of the intervention. These initial findings show proof of concept for this brief intervention in a cardiac-specific behavioral medicine setting.